AT&T just sold off their wireless business to Cingular, so there will probably be plenty of problems for the next year as they merge their systems together.
I work for T-Mobile, so if you have any questions, ask away. The call quality I've experience in Oregon with them has been better than I had with AT&T and not quite as good as when I had Sprint. Unfortunately, Sprint's customer service was bellybutton . . . consistantly. And in an attempt to make it even worse, they were starting to charge for certain calls to customer service in the last few months I had service with them - don't know if they've abandoned that stupid idea or not. Never had any beefs with AT&T, they always seemed helpful, except for when I lowered my rate plan in the last month before I cancelled...they told me they couldn't tell me how many minutes I'd used on my plan. Three different calls, all the same answer. I thought that was strange. I had Verizon a long time ago, so it wouldn't be fair to compare call quality, but they had a great coverage area...a friend still uses them and has no complaints.